(CNN) --Sen. John Kerry holds a dominant edge over his Democratic presidential rivals in a nationwide CNN/Time poll released Saturday night, but all the leading Democrats trail President Bush in hypothetical one-on-one matchups -- though results pitting Bush against Kerry or Sen. John Edwards fell within the poll's margin of error.

Kerry, of Massachusetts, was preferred by 43 percent of the 377 registered Democrats or Democratic-leaning voters.

Edwards, a North Carolina senator, polled 18 percent, and retired Gen. Wesley Clark was the choice of 11 percent.

In a hypothetical matchup against Bush, Kerry trailed 50 percent to 48 among likely voters with a 4.1 percentage-point margin of error. For Kerry, it was big improvement from a month ago, when he trailed Bush 54-40 in a similar comparison.

Edwards also trailed Bush in a hypothetical contest, 52 to 46 percent -- a better showing than a month ago, when he trailed 53 to 39.

In a hypothetical matchup with Clark, Bush led 55-41 percent.

The president's approval rating was at 54 percent, with 42 percent disapproving of his performance in office. Bush's approval rating has been remarkably stable in the Time/CNN poll, since July never dipping below 52 percent or above 55 percent.

Kerry's advantage over other Democrats mirrors his remarkable surge in the opening rounds of primaries and caucuses. The Massachusetts senator won nine of the first 11 contests, including projected wins in the Washington and Michigan caucuses Saturday.

In a nationwide Time/CNN poll taken just days before the January 19 New Hampshire primary, Kerry and Edwards were tied for third place with 9 percent apiece. Howard Dean led with 19 percent, while Wesley Clark had 14 percent.

One sign of trouble

One sign of trouble for Kerry in the new poll: 21 percent said the fact he represents Massachusetts, "a state that is more liberal than most others," would make them less likely to vote for him. Ten percent said it makes him more likely to get their vote, while 67 percent said it made no difference.

A significant majority in the poll found both Kerry and Bush "likeable," but respondents showed a high degree of cynicism about the electoral process.

Asked if the statement "would say anything to get elected president" applies to Kerry, 44 percent said yes, while just 40 percent said no.

Asked the same of Bush, 52 percent said yes, while 45 percent said no.

The survey was conducted by telephone, February 5 and 6, interviewing 1,000 Americans age 18 and older.